Humanity has become obsessed with breaking its limits, creating new records only to break them again and again. In fact, our cities’ skylines have always been defined by those in power during every period in history. At one point churches left their mark, followed by public institutions and in the last few decades, it’s commercial skyscrapers that continue to stretch taller and taller.

But when it comes to defining which buildings are the tallest it can get complicated. Do antennas and other gadgets on top of the building count as extra meters? What happens if the last floor is uninhabitable? The Council on Tall Buildings and Urban Habitat (CTBUH) has developed their own system for classifying tall buildings, measuring from the “level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment.” Using this system more than 3,400 buildings have been categorized as over 150 meters tall.

We take a look at world’s 25 tallest buildings, according to the CTBUH. List updated on January 2019.